Saner Memory Management + Fix Error Handling, Confirmed working on macOS

Author: donn

Makefile

@@ -6,20 +6,25 @@ SOURCES = $(SRC_DIR)/libparse_wrap.cpp $(SRC_DIR)/py_iostream.cpp $(SRC_DIR)/lib
 OBJECTS = $(patsubst %.cpp,%.o,$(SOURCES))
 HEADERS = $(SRC_DIR)/libparse.h $(SRC_DIR)/py_iostream.h $(SRC_DIR)/stdio_filebuf.h
 
-CXX = clang++
+CXXFLAGS += -g -std=c++11 -I$(shell python3 -c "import sysconfig; print(sysconfig.get_path('include'))")
+LDFLAGS += -g -L$(shell python3 -c "import sysconfig; print(sysconfig.get_path('stdlib'))")
+EXT = .so
 
-CXXFLAGS += -stdlib=libc++ -g -std=c++11 -I$(shell python3 -c "import sysconfig; print(sysconfig.get_path('include'))")
+ifeq ("$(shell uname)", "Darwin")
+LDFLAGS += -dynamic -undefined dynamic_lookup
+else
+LDFLAGS += -shared
+endif
 
-
-all: _libparse.so
+all: _libparse$(EXT)
 patch: $(SRC_DIR)/libparse.cpp $(SRC_DIR)/libparse.h
 swig_out: $(SWIG_OUT)
 
-_libparse.so: $(OBJECTS)
-	$(CXX) -shared $^ -o $@
+_libparse$(EXT): $(OBJECTS)
+	$(CXX) $(LDFLAGS)  $^ -o $@ 
 
 $(OBJECTS): %.o : %.cpp $(HEADERS)
-	$(CXX) -fPIC -o $@ -c $(CXXFLAGS) -DFILTERLIB $<
+	$(CXX) $(CXXFLAGS) -fPIC -o $@ -c -DFILTERLIB $<
 
 $(SWIG_OUT): $(SWIG_IN) $(HEADERS)
 	swig -c++ -o $(SRC_DIR)/libparse_wrap.cpp -oh $(SRC_DIR)/libparse.h -python $<

libparse/libparse.i

@@ -21,9 +21,10 @@
 
 %typemap(in) std::istream& {
     try {
-        $1 = new PyIStream($input);
+        $1 = PyIStream::make_from($input);
     } catch (std::runtime_error &e) {
-        PyErr_SetString(PyExc_TypeError, e.what());
+        std::cerr << e.what() << std::endl;
+        SWIG_exception(SWIG_TypeError, e.what());
     }
 }
 

libparse/py_iostream.cpp

@@ -1,12 +1,12 @@
 #include "py_iostream.h"
 
-buffer_pair from_pyobject(PyObject *pyfile)
+PyIStream *PyIStream::make_from(PyObject *pyfile)
 {
     if (pyfile == Py_None) {
         throw std::runtime_error("None is not a valid input stream");
     }
     auto fileno = PyObject_GetAttrString(pyfile, "fileno");
-    if (fileno == Py_None) {
+    if (!fileno) { // NOT NONE!! NULL!!
         throw std::runtime_error("Passed object has no fileno() method");
     }
 
@@ -20,5 +20,5 @@ buffer_pair from_pyobject(PyObject *pyfile)
         throw std::runtime_error("Failed to open input stream");
     }
 
-    return buffer_pair(new stdio_filebuf<char>(f), f);
+    return new PyIStream(new stdio_filebuf<char>(f));
 }

libparse/py_iostream.h

@@ -2,66 +2,18 @@
 #include "Python.h"
 #include "stdio_filebuf.h"
 
-typedef std::pair<stdio_filebuf<char> *, FILE *> buffer_pair;
-// buffer_pair from_pyobject(PyObject *pyfile);
-
-// struct PyIStream : public std::istream {
-//     PyIStream(PyObject *pyfile) : buffers(from_pyobject(pyfile)), std::istream(std::get<0>(buffers)) {}
-
-//     ~PyIStream()
-//     {
-//         FILE *f;
-//         stdio_filebuf<char> *buf;
-
-//         if ((f = std::get<1>(buffers))) {
-//             fclose(f);
-//         }
-//         if ((buf = std::get<0>(buffers))) {
-//             delete buf;
-//         }
-//     }
-
-// private:
-//     buffer_pair buffers;
-// };
-
 struct PyIStream : public std::istream {
-    PyIStream(PyObject *pyfile)
-    {
-        if (pyfile == Py_None) {
-            throw std::runtime_error("None is not a valid input stream");
-        }
-        auto fileno = PyObject_GetAttrString(pyfile, "fileno");
-        if (!fileno) {
-            throw std::runtime_error("Passed object has no fileno() method");
-        }
-        fd = PyObject_AsFileDescriptor(pyfile);
-        if (fd == -1) {
-            throw std::runtime_error("Failed to get file descriptor");
-        }
-
-        f = fdopen(fd, "r");
-        if (!f) {
-            throw std::runtime_error("Failed to open input stream");
-        }
+    PyIStream(stdio_filebuf<char> *buffer) : std::istream(buffer), buffer(buffer) {}
 
-        buf = new stdio_filebuf<char>(f);
-
-        init(buf);
-    }
+    static PyIStream *make_from(PyObject *pyfile);
 
     ~PyIStream()
     {
-        if (f) {
-            fclose(f);
-        }
-        if (buf) {
-            free(buf);
+        if (buffer) {
+            delete buffer;
         }
     }
 
 private:
-    int fd = -1;
-    FILE *f = nullptr;
-    stdio_filebuf<char> *buf = nullptr;
+    stdio_filebuf<char> *buffer = nullptr;
 };

setup.py

@@ -30,6 +30,7 @@
     swig_opts=["-c++"],
     sources=[
         "libparse/libparse.cpp",
+        "libparse/py_iostream.cpp",
         "libparse/libparse.i",
     ],
     include_dirs=[

shell.nix

@@ -4,10 +4,12 @@
 with pkgs; mkShell {
     buildInputs = [
         swig
-        clang_16
-        clang-tools_16
+        clang_14
+        clang-tools_14
         python3Full
-        valgrind
         twine
     ];
+
+    CC = "clang";
+    CXX = "clang++";
 }